Gas-analyzing apparatus



Jan. 21, 1930. E. PICK GAS ANALYZING APPARATUS Original Filed Aug. 1,1927 m 2 m p Patented Jan. 21,1930

new rim, or. new Your, n.1,, assrcmon To "run umwm conrm, orinnw Yemen,Y., A. coaromnox oria anawalauzeasannyzme' Bran urns Appllcation'file dAugust 1,1921; Serial'Np.209,764. Renewed'Septembe r 21,1929. i

This invention relates to gas analyzing ap-.

paratus;'and it comprises the combination of a gasanalyzing or similarapparatus having metal parts with a gas purifying chamber 5 containing arenewable charge. of steel wool;

' all as more fully hereinafter set forth and as m necessary claimed. 7p Gas analyzing apparatus have usually metal parts and connections andit is therefore for accuracy of results that the entering gas besidesbeing freed of solid particles does not containanything which willcorrode for injure these metal parts. This result, however, is diflicultto accomplish, and- 5 particularly with flue gas,

I blast furnace gas, producer gas and the like. Fuels contain sometimessulfur. This sulfur burns to-SO or'SOgin the furnace; and when the linegases are 2 cooled down to room temperature some conf m Hgsog Orfurther, to the extent of their presence vitiate I 3 in practice tofilter it with that the apparatus will not gradually accu densationalways takes place, producing moisture which combines with the S0 01 S0to acids are highly corrosive to'most-metals and,

the results of a flue gas analyzer. Furthermore, much of the.mineralmatter carried by fluegas is very time, its fineness sometimesa'p proaching that of a'fume, and it is found hard such perfectionporous mass and imposes'no great fric ion on gas passing therethro'ugh;nevertheless, its action in removing even very'fine suspended matter isexceptionally thorough. Not being hygroscopic, it does not absorb andswellwith moisture inthe gas, as do cotton, sawdust,

to. and cause an increase in flow resista e partly n elevat on,illustratingthe use of a steel wool filter in connection with aflueg'as,

ance. Steel wool has great porosity, even when considerably. compressedand it does not pack and clog read ly as do cotton and other organicfiltering" materials. Neither does it tend to channel as does glassor-other' corrosive fumes abovereferred to.

'quite appreciable proportions of.

H SO respectively. I These mineral wool." Part 'of its great powe r forprocessof manufacture.

The most'i'mportant property of steel IWo0l in this relation is,however, cleaning action it exercisesthe commercial material carriesfrom-"the by removing tlio siderably more efficient other forms ofmetallic in this respect than iron, a fact possibly partly due to thehighly strained condition the very effective -It is conin which-themetal exists; due to cold-deformationduring manufacture, and possiblydue to the very large surfaces per unit of weight as well asper unit ofvolume. sary to heat the steel Wool or to use catalyzers in combinationwith it in order to obtain'the desired de-acidifying effect.

a In actual use in gas analyzing, I find with acid gases a steel woolfilter ordinaril "does Itis not necesnot last long, the acidconstituents in t e, as" v attacking it. Sometimes with aCo-grecorder'ga's'a steel wool charge may last in use on flue only a week beforereplacement'is. required;

In such a case, a charge of.-this wool corrodes A gradually, corrosionstarting at the inlet, and, V p

it; finally ever as o tions well. In practice, it is often desirable tocombine the steel-wool with a mechanical dust filter of some'other'type. For instance,

;a porous stony material such as carborundum, or sawdust forms a usefulpreliminary filter to remove coarse dust, prior to the passage of thegases through the steel wool. While I have foundthe steel wool 'byitselfhighly efiicient for my purpose, in somerelationsan admixture of otherfibers, such as cotton, may be used.

In the accompanying drawing, showing several forms of my'invention,

Figure 1 is a view partly in section and breaks down to apowder. Hows ngas there is still unchanged steel .wool in the path ofthe gases thefilter funca steel wool filter, also in connection with a flue gasanalyzer.

Referring'to Fig; 1, a flue gas sam la is drawn throughthe pipe2 fromthe no or boiler pass 1. The pipe 2 is sloped towards the outside sothat any condensedfmoisture flows to the water leg 3 whence it isdrained automatically. The tube 2 rises throu h the liquid seal 5 1n thefilter pot 4. The stee wool 8 is placed in the containerfi havin adividing wall! which does not extend al .the way to thei'top. The steelwool 8 is held in place by the steel wool holder 9 which is clamped onto the dividing wall 7. When the steel wool container 6 is ut in itsproper place in the filter pot 4, the iquid seal 5 prevents any gasleakage and also causes the gas to flow upwardly through the steel wool8 on the left hand side anddownwardl side of the dividing wall 7. Thegas then flows through the pipe 10 to the flue gas analyzer 11.

In Fig. 2, the combination of a steel wool filter with a orous stonefilter 12. is'shown. This porous lter is-located inside the flue 1 andattached'to the pipe 2 by means oi the coupling 13. This arrangement hasthe advantage that most of-the suspended matter is kept out of the'pipeline; The steel wool 8 is placed in the steel vwool container 14. Inorder to replace the steel wool it is only necessary to loosen the thumbscrews 17 whereupon the yokes 16 and covers 15 may be removed.

Where the gas temperature is very high a filter located 1n the gas ductcannot be used and an external filter'has to be employed instead. Thisarrangement is shown in Fig. 3. The gas sam le againis taken from thegas duct 1 and ows through the pipe 2 to the preliminary filtercontainer18 which has a removable cover 19. The container 18 holds sawdust,cotton or the like, 20, which is supported by a strainer plate 21. Fromthe preliminary filter the gas flows through pipe 22 to the steel woolcontainer 23 which is filled with steel wool"'8. Removable covers 24 areprovided for easy-replacement of the steel wool. From the steel woolfilter the gas flows through the pipe 10 to the flue gas analyzer It isof course not necessary that the preliminary filter and the steel woolfilter be physically separated. It is for instance possible to materialin the one half of the container 6 shown in Fig. 1, whereas the steelwool is on the right hand lace the preliminary filtering' for theroducts of combustion or flue gases from boiler furnaces, it is usefulin connection with any other analyzing or metering device having metalparts and dealing with gases which are, or may be, of acid nature.

What I claim is 1..Thecombination with a'gas measuring device havingmetallic parts which can be affected by fumes or impurities in the as,of a filter through which the gas flows efore reachin the measuringdevice, such filter comprising a mass of steel wool.

2. The combination with a gas measuring device having metallic partswhich can be affected by fumes-or impurities in the gas, of a filteringdevice through which the gas flows before reaching the measuring device,such filtering device comprising a compact mass of steel wool.

3. The combination with a gas measuring device having metallic partswhich can be affected by fumes or impurities in the gas, of a filteringdevice through which the gas flows before reaching the measuring device,such filtering device comprising a container, a mass of steel wooltherein, and a preliminary filter for removing coarser suspendedparticles from the gas before they reach the 30th day of July, 1927.

. ERIC PICK. 7

placed in the other half. Furthermore, if so desired, the steel wool 8can be mixed with cotton, excelsior or some other fiber in any of thesteel wool containers, 6, 14 or 23 shown in Figures 1, 2 and 3respectively.

\Vhile I have found the present invention of particularly great utilityin connection with mechanically operating CO recorders

